When the energy needed for bond making is the energy needed for bond breaking, the reaction is endothermic.

When the energy needed for bond making is higher than the energy needed for bond breaking, the reaction is endothermic.

Explanation:

An endothermic reaction is that in which the energy of the products or bond making is higher than the energy of the reagents or bond breaking, therefore needs energy to take place.

on passing the small ampere of electric current through the tube made of ar and hg of cfl generates uv rays which excites the fluorescent and thus emits the high radiation by consumption of just 5- 12 w in comparison to incandescent light which requires more power such as around 40 - 55 w to lighten.

moreover the life span of fluorescent or cfl is around 8000 h whereas the life span of incandescent is around 1200 h

hence, the building installed with incandescent lights bears more electricity bill.